1. Field of the Invention
The present invention relates to colorant-containing particles useful for various applications, and to dispersions containing same. The present invention also relates to polymer compounds useful for various applications, including dispersants.
2. Background Art
Electrophoretic display media, a type of memory displays, have been actively studied. For display, this display mode uses charged particles (electrophoretic particles), and applies an electric field to, for example, a cell sealing the electrophoretic particles and a dispersion medium between a pair of electrode substrates to alternately move the electrophoretic particles toward and away from the viewing surface and the back face.
The particles (electrophoretic particles) constitute an important factor in this technique, and various techniques have been developed. For example, various additives, such as dispersants, have been proposed to suppress aggregation of the electrophoretic particles. Dispersants having different charge polarity from the charge polarity of the particles are also proposed to improve the charge stability of the electrophoretic particles (for example, Patent Documents 1 and 2).
Patent Documents 1 and 2 disclose polymers produced by copolymerizing a monomer having an acidic group or a basic group, and a silicon-containing monomer. These publications also disclose adding the polymer to, for example, a display particle dispersion containing a silicone oil.